Personally, one of my favorite things about the game was that - until recently, it seems - strategy, clever play, and luck were emphasized in Elements. Now, emphasis is clearly on accumulating so many powerful cards that only another rediculously powerful deck can compete with yours. The victory goes to the person who has the most, most-powerful cards - cards which must be gained almost entirely by grinding. It's all about increasing your grind level instead of your creativity, cleverness, and thoughtfulness with the game.
I truly don't meant to be rude, but it sounds like you're playing a different game from the rest of us. What you're describing is absolutely NOT the case in Elements. Which PvP events are you participating in where you think people are beating you because their cards are better? Which cards are you talking about anyway? If it's upped cards, then most PvP events don't allow them; if it's nymphs you are talking about three or four players with enough of them to really create a standout advantage ... and by practice those players generally don't do that anyway.
I think what's happening is you are adopting a relative viewpoint. You have certain expectations based on the status quo of Elements -- which is that it's a strategy-focused game to the extreme, etc. And that's an accurate view. However, a slight shift in a different direction does not appropriately justify a statement that this game has become "all about grinding" ... and it is most fair to get better perspective on the issue by comparing the game with other games. Compared to most other games, this game is close to zero percent "about grinding" when it comes to being a skilled PvPer.
Imagine a more casual player's predicament.
I think the trouble is that you are considering yourself "in a predicament" in the first place. Let me phrase that perhaps more clearly: Being in a predicament within the confines of the game -- as in, you need to adjust your deck strategy -- is part of the game. Being in a predicament like that the game isn't fun anymore because it has stagnated, is a predicament on the design level and is somewhat exterior to the game. The two are very different, but you are considering an aspect of the first party to the second.
The relevance of what I'm saying is that wanting something to be easier for you within the game is not really a justification for altering the structure of the game. It is just a difficulty within the game itself. You might argue that it's a difficulty that makes things "not fun" but at the end of the day it's your definition of what is fun that is the variable. By many, many gamers' standards the dynamic nature of a changing game environment, requiring strategy adjustments, is precisely what makes a game fun!
Anyway, those are just my two cents. I do think your concerns are perfectly valid
and hopefully there are still applications for your older upped deck. But you should consider that if you invested a considerable amount of time and effort into building the deck in the first place (which seems probable), then there's really no external logical reason why it should forever remain the best deck and therefore your deckbuilding days are forever over. On the contrary, I would consider that a form of stagnation of the game and quite a bad thing. Luckily the structure of the game is such that instead of deep sixing the deck altogether (which nonetheless is a time-saving option if you prefer it), you can keep it and build a new deck, ending up with two.
I hope my comments were helpful and didn't come across as antagonistic. I think your points are valid but I think it could be helpful if you try to see the situation from a slightly different viewpoint.